Chapter 8.2, Problem 16CYU

To determine

The length of the actual car .

Answer to Problem 16CYU

  $C\text{11}\frac{3}{8}\text{feet}$

Explanation of Solution

Given:

A scale drawing of a car is 13/4 and also scale is given $\text{1inch}=\frac{7}{2}\text{feet}$ .

Concept Used:

Rules of Addition/ Subtraction:

• Two numbers with similar sign always get added and the resulting number will carry the similar sign.
• Two numbers with opposite signs always get subtracted and the resulting number will carry the sign of larger number.

Rules of Multiplication/ Division:

• The product/quotient of two similar sign numbers is always positive.
• The product/quotient of two numbers with opposite signs is always negative.

Calculation:

In order to find the length of cars we use the unitary method with the given scale and simplify further as shown below,

  $\begin{array}{c}\text{1inch}=\frac{7}{2}\text{feet}\\ \text{So,}\\ \frac{13}{4}\text{inch}=\frac{7}{2}\times \frac{13}{4}\text{feet}\\ \text{=}\frac{91}{8}\text{feet}\\ \text{=11}\frac{3}{8}\text{feet}\end{array}$

Thus the actual length of car $\text{11}\frac{3}{8}\text{feet}$ and option C is correct.